Rapid developing photographic materials containing arginine

ABSTRACT

Improved process for rapid development of photographic material, particularly a process for developing a latent image formed upon a photographic silver halide emulsion layer by treating the element with an alkaline activator solution in the presence of arginine.

United States Patent Tatsuya Tajima; Katsumi I-layaski, both of Kanagawa, Japan 884,436 Dec. 12, 1969 Oct. 26, 1971 Fuji Photo Film Co., Ltd. Kanagawa, Japan Continuation-impart of application Ser. No. 536,979, Mar. 24,1966, now abandoned.

Inventors Appl. No. Filed Patented Assignee RAPID DEVELOPING PHOTOGRAPHIC MATERIALS CONTAINING ARGININ E 10 Claims, 4 Drawing Figs.

U.S.'Cl 96/66.3, 96/95 Int. Cl E03c 5/30,

E03c l/06, 1503c 1/48 REFLECTIVE DENSITY (D) ARGlNlNE-CONTAINING [50] Field of Search 96/66.3, 95

[56] References Cited UNITED STATES PATENTS 3,190,752 6/1965 Hayakawa 96/107 OTHER REFERENCES Photographic Science and Engineering, Vol. 6, No. 5, 1962 pp. 272 275 Chem. Absts. 1946 p. 528 Vol. 46

Himary Examiner-Norman G. Torchin Assistant ExaminerMary F. Kelley Attorney-Sughrue, Rothwell, Mion, Zinn & MacPeak ABSTRACT: Improved process for rapid development of photographic material, particularly a process for developing a latent image formed upon a photographic silver halide emulsion layer by treating the element with an alkaline activator solution in the presence of arginine;

2 (0) ARGININE- FREE LOG E PATENTEUBET 2 6 IBII LOG E 5 E22 magma LOG E- HG] PRIOR ART ,PRIOR ART Ewza $552 LOG E FIG. 3

INVEINTORS Am M M I AMHI ufl Mm WW 0 MM R T K law A ATTORNEYS RAPID DEVELOPING PHOTOGRAPHIC MATERIALS CONTAINING ARGININE CROSS-REFERENCE TO RELATED APPLICATION The present application is a continuation-in-part of Ser. No. 536,979, filed Mar. 24, 1966, now abandoned, by the same inventors as the present application.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to photography and, more particularly, to an improvedmethod of developing photographic silver halide emulsions.

2. Description of the Prior Art In conventional photographic processes, exposed silver halide emulsion layers are developed in a solution generally termed the developer, which contains one or more photographic developing agents. It is then fixed, and finally water-rinsed.

These treatments consume an appreciable amount of time. Therefore, many attempts have been made for reducing the processing period.

A known rapid process of producing photographic prints is to employ as the photographic elements, an element comprising a support, a silver halide emulsion layer, and an organic colloid layer; incorporated in at least one of said layers is at least one developing agent, to expose imagewisely the element, and to treat it with an alkaline activator" solution in order to activate the developing agent, thereby producing a silver image in the element.

It is possible to carry out the process of the aforesaid rapid development by feeding the exposed photographic element through the nip of a pair of rollers, which apply the activator solution to it, thus rendering possible the production of prints in a rapid and reliable manner.

Arginine has been known as a development-accelerating agent (see Miura et al., Development-Accelerating Effect of Arginine, Photographic Science and Engineering, Vol. 6, pp. 272-275, I962). However, in the Miura et al. article, the development-accelerating effect is to improve the sensitivity of the light-sensitive material as shown in FIG. 1. In contradistinction, the present invention has for its object to (a) improve the gradient, and (b) to increase the image density and to improve the color tone of the light-sensitive material. These effects (a) and (b) are shown in FIG. 2.

Miura et al. disclose various experiments which allegedly show the effect of arginine in accelerating development using a formaldehyde-hydroquinone developer. Particularly, in FIG. 4, and in the corresponding text, it is disclosed that, when comparing emulsions containing arginine with those which do not, no development-accelerating effect of arginine is observed when a photosensitive material having an emulsion layer is developed with a D-85 developer to which has been added 30 grams of sodium' sulfite.

In the experiments described in the Miura et a]. article, D- 85 developer is employed, which implies the development of lithographic film. That is, a lithographic film Is one coated with such an emulsion to give high contrast, high density value and high resolving power on a film base, and is developed by D-85 developer after image exposure. The D-85 developer has the ability to make an image having a high density value and a high gamma for a short period of time. D-85 is a developer produced by Eastman Kodak and essentially is a developer of the paraformaldehyde-hydroquinone series, as shown by the following composition:

Sodium sulfite 30.0 g. Paraformaldehyde 7.5 g. Sodium bisulfite 2.2 g. Boric acid 7.5 g. Hydroquinone 22-5 g. Potassium bromide l.6 g. Water to I cc.

In this developing liquid, the following reaction takes place:

As a result, in the liquid, the concentration of SO, ion is decreased, and formaldehyde bisulfite and caustic alkali are produced. Thus, the amount of S0 ion is considerably less than that in the conventional MQ developer (metolhydroquinone). The concentration of this ion is thought to have a remarkable influence on infectious development, and in a strong alkaline hydroquinone developer, such as 1 gram of 80;, ion per 1 liter of solution, the infectious development effect is most remarkable, and the gamma of the characteristic curve is abruptly elevated. Further, when using this type of developer, the cutting of foot in the characteristic curve of the lithographic film is improved. The exposed lithographic film, when treated with a D type developer, starts to develop an image after a certain induction time from the start of development, and rapidly increases to a high density value for a short time. Such a development is commonly termed an infectious development. This infectious development is characterized in that the concentration of S0 ion is very small.

However, in the Miura et al., article, in view of the fact that, in the experiment described in FIG. 4, when sodium sulfite is added in excess, it is regarded as appropriate that it is not an infectious developer, but rather a developer for forming a general image. According to the experimental results shown in FIG. 4 of Miura et al., when such a developer is used, it is disclosed that arginine did not show any development-accelerating effect in such case.

Accordingly, it is an object of the present invention to provide a process for developing a latent image formed on a photographic silver halide emulsion layer of a photographic element whereby photographic images of superior quality are produced.

A further object of the present invention is to improve the gradient of the light-sensitive material.

A still further object of the present invention is to increase the image density and to improve the color tone of the lightsensitive material.

SUMMARY OF THE INVENTION The present inventors have found that arginine is an effective development accelerating agent when employed in the aforesaid rapid development process.

Arginine is incorporated in at least one of the following: a silver halide emulsion layer, an organic colloid layer adjacent to the emulsion layer, or an alkaline activator solution.

When arginine is added in the activator solution, it can be incorporated in an amount of from 0.1 to l0 grams and preferably 0.2 to 5 grams per 1 liter of the solution. When arginine is incorporated in the emulsion layer, it can be incorporated in an amount of from 0.l to 50 grams and preferably 2 to 20 grams per 1 kilogram of silver halide emulsion, and in the organic colloid layer from 0.1 to 4 grams per 1 gram of the organic colloid.

BRIEF DESCRIPTION OF THE DRAWINGS.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Arginine is effective in a rapid development process for the development of photographic materials containing developing agents, by treatment simply with an alkaline solution. By applying arginine according to the present invention, the density and gradation of the obtained prints, and the tone of the silver image is remarkably improved.

In addition, any arginine salt may be employed; such as arginine hydrochloride, arginine carbonate, arginine sulfate, etc. Any salt is operable since the salt dissociates into arginine in the developing agent, and thus the desired effect is achieved.

The arginine used in our invention has been found useful when employed in conjunction with a gelatino silver halide emulsion, such as silver chloride, silver chlorobromide, silver chloride containing a trace of iodide, and silver chlorobromide containing a trace of iodide. The developing agents which can be incorporated into the emulsions according to an embodiment of this invention comprise developing agents such as hydroquinone, catechol, l-phenyl-3-pyrazolidone, monomethyl-p-aminophenol sulfate and the like; either alone or mixtures thereof.

The organic colloid layer adjacent to the emulsion layer according to the present invention may comprise gelatin, or other colloids such as cellulose derivatives, natural and synthetic water soluble polymers, etc.

With respect to the Miura et al. article mentioned above, as is clear from the data given therein, P-formaldehydehydroquinone type developers were employed. Thus, a specific high contrast effect usually called infectious development is obtained.

When the silver halide of the photographic silver halide light-sensitive film is developed in the developer, the hydroquinone in the developer is converted into an oxidation product such as semiquinone or quinone (1). However, when a large amount of sulfite ion is present in the developer, the semiquinone and quinone thus formed are very unstable and are immediately converted into hydroquinone sulfonate, whereby the high contrast specific to lithographic development is lost. Yule (2), Wood (3), and Vanreusel (4), Umberger (5), Zwicky (6) et al., have explained these phenomena from the fact that the high contrast images are obtained when the semiquinone or quinone is formed by the development in the sulfite ion free developer. That is, when semiquinone is accumulated, the development of the silver halide particles near the development centers, having a low developing rate, is accelerated to cause the infectious development effect, whereby the image density is rapidly increased, while no such development effect is provided to the silver halide particles which are not developed. As a result of these phenomenona, the extra high contrast is obtained. On the other hand, when no sulfite ions are present in the developer, semiquinone is not accumulated and hence high contrast is not obtained. The Miura et al. experiments were conducted with the D-85 type developer having such a technical background. However, among the results disclosed by M iura et al., the results shown in FIG. 4 are different from the other experimental results wherein the above-mentioned sulfite ion-free developer was employed. That is, in the experiments shown in FIG. 4, a composition prepared by adding to the 0-85 developer 30 grams per liter of sodium sulfite was used as the developer. This developer is a developer of the type showing no infectious development, which has generally been used. However, Miura et al. describe, as the results shown in FIG. 4, that when such a developer was used, the effect of arginine contained in the silver halide emulsion layer was not confirmed. Therefore, in order to confirm that the addition of arginine gives no effect with respect to the Miura et al. developer used in the experiment shown schematically by FIG. 4, that is, the developer for lithographic film which contains sodium sulfite, while a developer of the present invention for a photographic-light-sensitive material of a type where the silver halide emulsion layer contains a developer, the addition of arginine is remarkable even when the activator solution contains sodium sulfite, the following experiments were conducted.

The above-noted numerals correspond to the following references:

1. H. G. Fitzky, J. Eggers, K. Frank: Photo. Korr., Vol. 103, page 66 (1967);

2. J. A. C. Yule: J.Frankl. Inst. Vol. 239, page 22l (1945);

3. H. W. Wood: J. Photo. Sci., Vol. 12, page 5(1964):

4. G. Vanreusel, R. Verbrugghe: Reprographie l Internationaler Kongress Koln l 963 5. J. Q. Umberger: Photo. Sci. Eng, Vol. 10, page 8 (1966);

6. H. Zwicky: Photo. Korr., Vol. l02,page ll (1966);

7. T. J. James: Photo. Sci. Eng., VOL 12, page 67 (I968).

EXPERIMENT I This experiment was designed to reconfirm the experimental results shown in FIG. 4 of the Miura et al. article. Two samples of silver chlorobromide emulsions (50 mole percent bromide) were prepared and to one of them was added 50 ml./kg. of an aqueous 20 weight percent solution of arginine chloride. Each of the silver halide emulsions was then applied to a baryta paper to provide two kinds of light-sensitive papers. When each of the light-sensitive papers was exposed and developed in PQ developer, used for general photographic portrait paper, containing phenidone (l-phenyl-3- pyrazolidone) and hydroquinone, the characteristic curves. (shown in FIG. 4) were obtained. The content of sodium sulfite in the developer was 15 grams per liter. The development was performed at 20C., and for a period of 60 seconds. From the characteristic curves in FIG. 4, the following values were obtained:

ES DS Gamma $1.0

Arginine-free sample (A) 1. 04 1. 71 2. 00 l, 070 Arglnine-added sample (B) 1. 15 1.69 1.78 1, 030

NOTE.ES =log Exposure Scale; DS Density Scale; Gamma Bar- Gamma; S1.0=Exposure Index (D=l.0).

EXPERIMENT 2 This experiment was carried out in order to confirm that in a process for developing a photographic light-sensitive material of a type having a silver halide emulsion layer containing a developer, in an alkaline solution containing no developer, :1 development accelerating effect (i.e., the increase of image density) was remarkably effected by the addition of arginine, even when the alkaline solution contained sodium sulfite.

Two kinds of silver chlorobromide emulsions (60 mole percent bromide) were prepared and to one of them was added 50 mL/kg. of an aqueous 20 weight percent solution of arginine hydrochloride. Each of the emulsions was then applied to a baryta paper to provide a light-sensitive paper. In addition said emulsions each contained 20 grams of hydroquinone per kg. of emulsion. The light-sensitive papers were exposed and processed in an activator having the following composition to provide photographic images:

Potassium hydroxide 30 g. Sodium sulfite (anhydrous) 50 g. Potassium bromide 5 3. Water to make I liter The photographic images were then stabilized in a stabilizing solution having the following composition:

Ammonium thiocyanate 33 g. Sodium orthophosphate 10 g. Disodium orthophosphate 20 3. Potassium pyrcsulfite l20 g. Cobalt sulfate 0.3 g. l-phenyl-5-mercaptotetrazole (0.1% methanol solution) 20 ml. Water to make I liter ES DS Gamma SLO Arginine-tree sample (A) 0.92 1. 76 2. 11 800 Arginine-added sample (B) 0. 88 1. 97 2. 60 880 The terms in the table above represent the same terms as in the results shown in experiment I.

As is clear from the above experiments, the results obtained in experiment 2 were completely difi'erent from the results disclosed in the Miura et al. article and the corresponding results in experiment I. That is, by experiment 2, it was confirmed that although a large amount of sodium sulfite was present during the development, as in the cases of the aforesaid two experiments, by the addition of arginine thereto, remarkable advantages such as an increase in the bar-gamma value and the density scale value were obtained, owing to the differences in the structure of the photographic light-sensitive materials. (i.e., a developer is incorporated in the silver halide emulsion layer of the light-sensitive material used in experiment 2) and in the manner of developing, i.e., the photographic images were stabilized in experiment 2).

The aforesaid rapid development process is thus more effective when combined with a stabilization process in which a developed silver image is stabilized by treatment with a solution of a compound which forms a light-inert silver complex by reaction with undeveloped silver halide.

Our invention will be further illustrated by reference to the following specific examples.

EXAMPLE I Potassium hydroxide ll 30 grams Sodium sulfite (anhydrous) 40 grams Potassium bromide 5 grams Water to make I liter The samples were immediately thereafter fixed and washed. The sensitometric values obtained are tabulated below:

Arginine Hydrochloride Addition Amount in the Emulsion Density Scale Bar-Gamma (ml. per Kilogram) EXAMPLE 2 An emulsion was prepared by adding grams of 65 hydroquinone and 2.5 grams of I-phenyl-B-pyrazolidone with sufficient stirring to l kilogram of a gelatino silver chlorobromide emulsion and adjusting the pH of the mixture to 5.0. ml. of an 18 percent aqueous solution of arginine sulfate was added to separate portions of the emulsion prepared above. These separate portions were then coated on separate sheets of baryta paper and samples of each coating were then exposed through-a step wedge. The emulsion was developed in an activator having the following composition:

A B Sodium hydroxide 55 grams 55 grams Sodium sulfite (anhydrous) 30 grams 30 grams Potassium bromide 0.5 gram 0.5 gram Arginine carbonate (5% aqueous sol.) 0 ml. l0 ml. Water to make I liter I liter When arginine carbonate was added to the activator, a good quality print having a higher density then in the activator not containing arginine was obtained, as shown below:

Arginine Carbonate Concentration in the Density Bar- Activator Scale Gamma (ml. per liter) EXAMPLE 3 A 8 Sodium hydroxide 58 grams 58 grams Sodium sulfite (anhydrous) 23 grams 23 grams Potassium bromide 0.4 gram 0.4 gram Arginine hydrochloride (20% aqueous solution) 0 ml. 10 ml. Water to make 1 liter l liter and immediately thereafter said coating were stabilized by applyihg a stabilizing solution having the following composition:

Ammonium thiocyanate 300 grams Sodium orthophosphate l0 grams Disodiurn orthophosphate 20 grams potassium phyrosulfite I20 grams Cobalt sulfate 0.3 gram l-phenyl-$-mercaptotetrazole (0.l% methanol solution) 20 ml. Water to make I liter The coating film was then dried and a good quality print film was obtained in a few seconds. The efiect of the arginine concentration is shown below.

Bar- Gamma Arginine Concentration in the Activator Density Scale (ml. per liter) Thus, it is clear from the above experimental results that the effects of adding arginine to an emulsion are peculiar to the development/stabilization system. As mentioned above, the development accelerating effect of arginine is remarkably influenced by the light-sensitive material, that is, the composition of the silver halide emulsion layer and the manner of processing.

What is claimed is:

l. A process for developing a latent image formed on a photographic silver halide emulsion layer of a photographic element, said layer containing at least one developing agent,

which comprises treating said element with an alkaline activator solution in the presence of a member selected from the group consisting of arginine and arginine salts.

2. The process as in claim 1 wherein said arginine or its salt is incorporated in said emulsion layer.

3. The process as in claim 2 wherein said member selected from the group consisting of arginine and arginine salts is incorporated in said emulsion layer in an amount of from 0.1 to 50 grams per 1 kilogram of said emulsion.

4. The process as in claim 1 wherein said member selected from the group consisting of arginine and arginine salts is incorporated in said alkaline activator solution.

5. The process as in claim 4 wherein said member selected from the group consisting of arginine and arginine salts is incorporated in said alkaline activator solution in an amount of from 0.l to grams per 1 liter of said alkaline activator solution.

6. The process as in claim 1 wherein said developing agent is selected from the group consisting of hydroquinone, catechol, l-phenyl-3-pyrazolidone, mono-methyl-p-aminophenol sulfate and mixtures thereof.

7. The process as in claim 6 wherein the additional step of stabilizing the photographic image is performed.

8. A process for developing a latent image formed on a photographic silver halide light-sensitive emulsion layer of a photographic element, said layer containing a developing agent selected from the group consisting of hydroquinone,

catechol, l-phenyl -3-pyrazolidone, mono-methyl-paminophenol sulfate and mixtures thereof which comprises treating said element with an alkaline activator solution which contains from 0.1 to 10 grams, per 1 liter of solution, of a member selected from the group consisting of arginine, arginine hydrochloride, arginine sulfate and arginine carbonate.

9. A process for developing a latent image formed on a photographic silver halide light-sensitive emulsion layer of a photographic element said layer containing a developing agent, wherein said emulsion layer contains from 0.1 to 50 grams per 1 kilogram of emulsion of a member selected from the group consisting of arginine, arginine hydrochloride, arginine carbonate and arginine sulfate, which comprises treating said element with an alkaline activator solution containing from 30 to 50 grams of sodium sulfite per 1 liter of activator solution.

10. A developing process as in claim 8, wherein said activator solution contains from 30 to 50 grams of sodium sulfite per 1 liter of activator solution, and further comprising the additional step of stabilizing the photographic image is performed.

UNITED STATES PATENT ()FFICE CERTIFECATE OF fiORRECTION Patent No. 9 Dated October 26, 1971 Inventofls) Tatsuya Tajima and Katsumi Hayaski It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Page 1, column 1, line 10, delete the period following the word abandoned" and insert claiming priority from March 24, U365, based on Japanese Patent Application Serial No. 40-16815.

Signed and sealed this 25th day of A ril 1972.

(SEAXL) Attest:

EDWARD MELETCHER, JR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents USCOMM'DC B0375-PG9 

2. The process as in claim 1 wherein said arginine or its salt is incorporated in said emulsion layer.
 3. The process as in claim 2 wherein said member selected from the group consisting of arginine and arginine salts is incorporated in said emulsion layer in an amount of from 0.1 to 50 grams per 1 kilogram of said emulsion.
 4. The process as in claim 1 wherein said member selected from the group consisting of arginine and arginine salts is incorporated in said alkaline activator solution.
 5. The process as in claim 4 wherein said member selected from the group consisting of arginine and arginine salts is incorporated in said alkaline activator solution in an amount of from 0.1 to 10 grams per 1 liter of said alkaline activator solution.
 6. The process as in claim 1 wherein said developing agent is selected from the group consisting of hydroquinone, catechol, 1-phenyl-3-pyrazolidone, mono-methyl-p-aminophenol sulfate and mixtures thereof.
 7. The process as in claim 6 wherein the additional step of stabilizing the photographic image is performed.
 8. A process for developing a latent image formed on a photographic silver halide light-sensitive emulsion layer of a photographic element, said layer containing a developing agent selected from the group consisting of hydroquinone, catechol, 1-phenyl--3-pyrazolidone, mono-methyl-p-aminophenol sulfate and mixtures thereof which comprises treating said element with an alkaline activator solution which contains from 0.1 to 10 grams, per 1 liter of solution, of a member selected from the group consisting of arginine, arginine hydrochloride, arginine sulfate and arginine carbonate.
 9. A process for developing a latent image formed on a photographic silver halide light-sensitive emulsion layer of a photographic element said layer containing a developing agent, wherein said emulsion layer contains from 0.1 to 50 grams per 1 kilogram of emulsion of a member selected from the group consisting of arginine, arginine hydrochloride, arginine carbonate and arginine sulfate, which comprises treating said element with an alkaline activator solution containing from 30 to 50 grams of sodium sulfite per 1 liter of activator solution.
 10. A developing process as in claim 8, wherein said activator solution contains from 30 to 50 grams of sodium sulfite per 1 liter of activator solution, and further comprising the additional step of stabilizing the photographic image is performed. 